Gas detectors are generally used by workers who are working in a potentially dangerous area where gas hazards may be present. These types of gas detectors can be designed to alert a user of the detector when a hazardous gas has been detected, but while the hazardous gas concentration is still low enough for the user to take action. Thus, a user can identify an impending hazard and remove himself from an area with a growing hazard before the user is incapacitated from the gas.
However, in some cases workers cannot remove themselves from a hazardous area on their own. For example, a worker may be exposed to a rapid release of a hazardous gas and be incapacitated before removing himself from the hazardous area. In these types of cases, it would be desirable to alert a rescue team or other authority that the worker is incapacitated.
Some systems and methods for reporting a man-down alarm are known in the art, but these known systems and methods have significant limitations. For example, some industrial radios known in the art incorporate a man-down alarm in which the user presses a button on the radio when he is in distress. This system enables a worker to signal for help and for a central office to arrange a rescue. However, this system presents at least three significant limitations.
First, this system does not function when the worker is already unconscious or otherwise incapacitated. Second, this system does not indicate who has triggered the alarm. And third, this system is prone to false alarms when an alert button is inadvertently pressed.
Some gas detectors known in the art include both a motion detector and alarm capability. When enabled, the gas detector generates an alarm if the detector has not moved for at least a predetermined period of time, for example, 30 seconds. Thus, in these types of detectors, the lack of movement indicates an incapacitated user, and an alarm is generated. However, this system presents at least two limitations.
First, there may be cases in which a user has not moved for the predetermined period of time, but is not unconscious or otherwise incapacitated. In these cases, the detector will generate a false alarm. And second, a man-down alarm generated by this system will be strictly local, and no remote call for assistance will be sent.
There is thus a continuing, ongoing need for improved systems and methods for detecting, generating, and reporting robust man-down alarms. Preferably, these systems and methods reduce false alarms, determine the likelihood of a man-down event occurring, and generate a remote alarm.